DBA Multistage Choke | SLB


Multistage choke

Drilling chokes in the field.

Cameron's DBA multistage choke is a multiple-pressure drop, anticavitation valve ideally suited for water injection. It controls the problems of cavitation, excessive noise, and vibration. To optimize performance, our DBA choke can be custom-designed to meet specific needs. A field-proven product, the DBA choke is backed by Cameron's commitment to service from our worldwide technical sales and service force.

Cavitation challenges

Cavitation threatens efficient flow control. Cavitation is the formation and sudden collapse of vapor bubbles in a flowing liquid. During the liquid’s passage through a valve, the pressure drops from the inlet pressure (P1) to a minimum pressure (PVC) in the vena contracta, just past the restriction. If the PVC falls below the liquid’s vapor pressure (PV), vaporization occurs and vapor bubbles form. As the liquid moves downstream from the vena contracta, the pressure recovers to P2. If this outlet pressure, P2, is above the vapor pressure, the vapor bubbles collapse. This effect induces high-pressure shock waves that can damage nearby metal surfaces. Other destructive effects of cavitation include high noise levels, vibration, and damage to valve and trim materials.

DBA Multistage Choke

Our solution

The DBA choke combats cavitation in water injection applications, including enhanced oil recovery and reservoir pressure maintenance. Its multiple-pressure drop design divides the normally large pressure drop into a series of smaller pressure drops. Cavitation is eliminated by keeping the pressure at the vena contracta, Pv, above the vapor pressure, PVC, of the liquid. The result is a valve that eliminates the threat of cavitation, reduces noise and vibration in downstream pipes and joints, improves control and performance, and increases production life.

Cameron assures optimized performance from the DBA choke. We work with you to design the valve and trim to meet your specific operation requirements. And, in some applications, it may be possible to retrofit your current MOV valves with a DBA choke trim.